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Biomass reforming by harvesting solar energy can provide green hydrogen. Current biomass photoreforming provides H2 erratically and in limited yield although efficiently, owing to intermittent features of solar light and incomplete degradation of biomass C-C bonds. Here, we detour the flaws by prioritizing conversion of carbohydrates to liquid hydrogen carriers (LHCs, consisting of HCOOH and HCHO), appropriate for transportation. Subsequently, the LHCs are fully decomposed, releasing only H-2 and CO2. This stepwise process enables complete scission of carbohydrate C-C bonds, affording 44 g of H-2 per kg of glucose thereof. Intermittent solar light provides the photoenergy and heat to split glucose car-bons to produce LHCs (2.5 mmol h(-1)) in a flow apparatus. This work demonstrates hydrogen production and storage by empha-sizing the complete scission of biomass C-C bonds.

The inefficient delivery of agrichemicals in agrifood systems is among the leading cause of serious negative planetary and public health impacts. Such inefficiency is mainly attributed to the inability to deliver the agrichemicals at the right place (target), right time, and right dose. In this study, scalable, biodegradable, sustainable, biopolymer-based multistimuli responsive core-shell nanostructures were developed for smart agrichemical delivery. Three types of responsive core/shell nanostructures incorporated with model agrichemicals (i.e., CuSOsub4/suband NPK fertilizer) were synthesized by coaxial electrospray, and the resulting nanostructures showed spherical morphology with an average diameter about 160 nm. Tunable agrichemical release kinetics were achieved by controlling the surface hydrophobicity of nanostructures. The pH and enzyme responsiveness was also demonstrated by the model analyte release kinetics (up to 7 days) in aqueous solution. Finally, the efficacy of the stimuli responsive nanostructures was evaluated in soil-based greenhouse studies using soybean and wheat in terms of photosynthesis efficacy and linear electron flow (LEF), two important metrics for seedling development and health. Findings confirmed plant specificity; for soybean, the nanostructures resulted in 34.3% higher value of relative chlorophyll content and 41.2% higher value of PS1 centers in photosystem I than the ionic control with equivalent agrichemical concentration. For wheat, the nanostructures resulted in 37.6% higher value of LEF than the ionic agrichemicals applied at 4 times higher concentration, indicating that the responsive core-shell nanostructure is an effective platform to achieve precision agrichemical delivery while minimizing inputs. Moreover, the Zn and Na content in the leaves of 4-week-old soybean seedlings were significantly increased with nanostructure amendment, indicating that the developed nanostructures can potentially be used to modulate the accumulation of other important micronutrients through a potential biofortification strategy.

Hydroxyapatite nanoparticles are popular tools in bone regeneration, but they have also been used for gene delivery and as anticancer drugs. Understanding their mechanism of action, particularly for the latter application, is crucial to predict their toxicity. To this end, we aimed to elucidate the importance of nanoparticle membrane interactions in the cytotoxicity of MG-63 cells using two different types of nanoparticles. In addition, conventional techniques for studying nanoparticle internalisation were evaluated and compared with newer and less exploited approaches. Hydroxyapatite and magnesium-doped hydroxyapatite nanoparticles were used as suspensions or compacted as specular discs. Comparison between cells seeded on the discs and those supplemented with the nanoparticles allowed direct interaction of the cell membrane with the material to be ruled out as the main mechanism of toxicity. In addition, standard techniques such as flow cytometry were inconclusive when used to assess nanoparticles toxicity. Interestingly, the use of intracellular calcium fluorescent probes revealed the presence of a high number of calcium-rich vesicles after nanoparticle supplementation in cell culture. These structures could not be detected by transmission electron microscopy due to their liquid content. However, by using cryo-soft X-ray imaging, which was used to visualise the cellular ultrastructure without further treatment other than vitrification and to quantify the linear absorption coefficient of each organelle, it was possible to identify them as multivesicular bodies, potentially acting as calcium stores. In the study, an advanced state of degradation of the hydroxyapatite and magnesium-doped hydroxyapatite nanoparticles within MG-63 cells was observed. Overall, we demonstrate that the combination of fluorescent calcium probes together with cryo-SXT is an excellent approach to investigate intracellular calcium, especially when found in its soluble form. Published version The authors acknowledge the Spanish Government for financial support through the PID2019-103892RB-I00/AEI/10.13039/501100011033 and MAT2017-83905-R projects, the “Ayudas para contratos predoctorales para la formaci ́on de doctores” scholarship (BES-2016-07672) of M. Bonany and a Ramon y Cajal grant of C. Mas-Moruno. They also thank the Generalitat de Catalunya for funding through project 2017SGR-1165, the Serra Hunter Fellowship of M.Espanol and the ICREA Academia Award of M-P. Ginebra.

Ustilaginoidea virens (teleomorph: Villosiclava virens) is an important fungal pathogen that causes a devastating rice disease. It can produce mycotoxins including sorbicillinoids. The biosynthesis and biological functions of sorbicillinoids have not been reported in U. virens. In this study, we identified a sorbicillinoid biosynthetic gene cluster in which two polyketide synthase genes UvSorA and UvSorB were responsible for sorbicillinoid biosynthesis in U. virens. In ∆UvSorA and ∆UvSorB mutants, the mycelial growth, sporulation and hyphal hydrophobicity were increased dramatically, while the resistances to osmotic pressure, metal cations, and fungicides were reduced. Both phytotoxic activity of rice germinated seeds and cell wall integrity were also reduced. Furthermore, mycelia and cell walls of ∆UvSorA and ∆UvSorB mutants showed alterations of microscopic and submicroscopic structures. In addition, feeding experiment showed that sorbicillinoids could restore mycelial growth, sporulation, and cell wall integrity in ∆UvSorA and ∆UvSorB mutants. The results demonstrated that both UvSorA and UvSorB were responsible for sorbicillinoid biosynthesis in U. virens, and contributed to development (mycelial growth, sporulation, and cell wall integrity), stress responses, and phytotoxicity through sorbicillinoid mediation. It provides an insight into further investigation of biological functions and biosynthesis of sorbicillinoids.

A comprehensive economic analysis of twenty light olefin production pathways has been performed, covering current and promising processes from fossil (petroleum, coal and natural gas) and renewable resources (biomass and CO2). Taking steam cracking of naphtha as the benchmark, this study gives an economic perspective and points out the bottleneck in different olefin production pathways. The assessment indicates that nearly all renewable pathways are economically unattractive currently and the raw material cost accounts for dominant contribution in most pathways, especially in the oil-, natural gas- and CO2-derived pathways. For the ways of methanol-to-olefins and methanol-to-propylene, fossil pathways are cost-competitive according to the date of current Chinese market prices. However, the price of feedstock hydrogen needs to be lowered by 55% to fill the cost gap between CO2-derived pathways and the benchmark. For the ways of oxidative coupling of methane and Fischer-Tropsch synthesis to olefins, fossil pathways enable cost-competitive processes by feedstock price fall, but further process improvement is required to approach benchmark in renewable pathways. Conditionally, a decrease in ethanol price by 45% can make ethanol dehydration pathway profitable. In addition, costs can reduce by 4%–23% in different pathways as the production scales expand from 100 to 1000 kt/a, resulting in a change from high cost to economic profit for some of the pathways. The results quantify the need for improvements on feedstock price, scale size and process improvement to achieve competitive production costs.

Development of an efficient cocatalyst system to eliminate the intrinsic conflict of the cross-interactions in a pair of cocatalysts and to overcome the extrinsic conflict of the reaction condition...

The decarboxylation of bio-derived fatty acids provides a sustainable pathway for the production of alkane products under mild conditions; however, products are generally obtained in low selectivity due to the uncontrollable reactivity of radical intermediates. Here we demonstrate that photogenerated radicals can be rapidly terminated by surface hydrogen species during photocatalytic decarboxylation of fatty acids on a hydrogen-rich surface that is constructed by the interactions between H2 and Pt/TiO2 catalyst, thereby greatly inhibiting oligomerization; Cn–1 alkanes can therefore be obtained from bio-derived C12–C18 fatty acids in high yields (≥90%) under mild conditions (30 °C, H2 pressure ≤0.2 MPa) and 365 nm light-emitting dode irradiation. Industrial low-value fatty acid mixtures (namely, soybean and tall oil fatty acids) can be transformed into alkane products in high yields (up to 95%). Our research introduces an efficient biomass-upgrading approach that is enabled by subtle control of the radical intermediate conversion on a heterogeneous surface. The photocatalytic decarboxylation of fatty acids affords alkanes under mild conditions, albeit with limited selectivity due to radical-mediated side reactions. Now, a hydrogenated Pt/TiO2 catalyst is introduced for the selective conversion of C12–C18 fatty acids into Cn–1 alkanes in quantitative yields.

PCTA is an important copolyester that has been widely used in our daily necessities. Currently, its monomers are industrially produced from petroleum-derived xylene. To reduce the reliance on fossil energy, we herein disclose an alternative route to access PCTA monomer (terephthalate/isophthalate = 2.4/1) in 61% overall yield using plant-based acrylate and acetaldehyde as the feedstocks. The process includes Morita-Baylis-Hillman (MBH) reaction of acetaldehyde with acrylate, subsequent one-step dehydration/Diels-Alder reaction with acrylate over H2SO4/SiO2 catalyst, and final Pd/C-catalyzed dehydrogenation. Besides, when varying the final step to hydrogenation, another important monomer UNOXOL™ diol (1,4-trans/1,4-cis/1,3-trans/1,3-cis = 5.2/2/2.5/1) can be produced in 67% overall yield.

Exploiting advantages of a double–type support to create an active site–isolated heterobifunctional catalyst is beneficial to an efficiently sequential organic transformation. Herein, an integrated soluble polymer and mesoporous silica as a double–type support to immobilize the tertiary amine–Ru/diamine–bifunctionality for the construction of an active site–isolated catalyst is developed, where the tertiary amine–functionality is tethered in the outer soluble polymer and chiral ruthenium/diamine–functionality is anchored within the inner mesoporous silica. Electron microscopy images, together with analyses of solid–state NMR spectra, disclose that catalyst possesses the uniformly distributive morphology with well–defined single–site ruthenium/diamine active centers. As envisaged, the heterobifunctional catalyst performs a highly efficient aza–Michael addition/asymmetric transfer hydrogenation enantioselective cascade reaction, where the outer tertiary amine–functionality enables a high reactivity to afford β–secondary amino ketones via an aza–Michael addition reaction of enones and amines, and the inner chiral ruthenium/diamine–functionality guarantees a high enantioselectivity to chiral γ–secondary amino alcohols via an asymmetric transfer hydrogenation of β–secondary amino ketones. Furthermore, this catalyst can also be recovered easily and recycled for six runs, showing a practical preparation of aryl–substituted γ–secondary amino alcohols.

Human hair keratin (HHK) has been successfully explored as raw materials for three-dimensional scaffolds for soft tissue regeneration due to its excellent biocompatibility and bioactivity. However, none of the reported HHK based scaffolds is able to replicate the strain-stiffening capacity of living tissues when responding to large deformations. In the present study, strain-stiffening property was achieved in scaffolds fabricated from HHK via a synergistic effect of well-defined, aligned microstructure and chemical crosslinking. Directed ice-templating method was used to fabricate HHK-based scaffolds with highly aligned (anisotropic) microstructure while oxidized dopamine (ODA) was used to crosslink covalently to HHKs. The resultant HHK-ODA scaffolds exhibited strain-stiffening behaviour characterized by the increased gradient of the stress-strain curve after the yield point. Both ultimate tensile strength and the elongation at break were enhanced significantly (~700 kPa, ~170 %) in comparison to that of HHK scaffolds lacking of aligned microstructure or ODA crosslinking. In vitro cell culture studies indicated that HHK-ODA scaffolds successfully supported human dermal fibroblasts (HDFs) adhesion, spreading and proliferation. Moreover, anisotropic HHK-ODA scaffolds guided cell growth in alignment with the defined microstructure as shown by the highly organized cytoskeletal networks and nuclei distribution. The findings suggest that HHK-ODA scaffolds, with strain-stiffening properties, biocompatibility and bioactivity, have the potential to be applied as biomimetic matrices for soft tissue regeneration. Agency for Science, Technology and Research (A*STAR) This research is supported by the Agency for Science, Technology and Research (A*STAR) under its Acne and Sebaceous Gland Program & Wound Care Innovation for the Tropics IAF-PP (H17/01/a0/008 & H17/01/a0/0L9).

Human hair fibers are structurally organized as a cortex protected by an outer scaly sheath (cuticle). Developing methods to isolate these two compartments will help to elucidate their roles in hair biology and develop potential applications. Herein, we developed enzymatic methods for human hair cuticle cell harvesting or removal. After a single treatment with esperase for three days, cuticle cells were released from hair shafts and effectively harvested by a series of filtration, centrifugation and resuspension steps. Separately, combining L-cysteine and either esperase or savinase could remove the entire cuticle layer to obtain descaled hair fibers. The physical and chemical structures, and performance of the isolated cuticle cells and descaled hair samples were characterized using electron microscopy, FTIR, solid state 13C NMR, TGA and DSC. Results show that the harvested cuticle cells contain mainly β-sheets and random coil structures, while descaled hair samples contain more α-helical structures. Harvested cuticle cells have greater thermal stability than the descaled hair samples below 260 C. The enzymatic methods developed in this study are convenient and easily controlled. They are effective not just for cuticle cell harvesting but also for surface modification and structure disintegration of hair fibers. Agency for Science, Technology and Research (A*STAR) Accepted version This research was supported by the Agency for Science, Technology and Research (A*STAR) under its Acne and Sebaceous Gland Program & Wound Care Innovation for the Tropics IAF-PP (H17/01/a0/008 & H17/01/a0/0L9), the China Scholarship Council (Grant No. 201906790039 to N.Z.), and the National Natural Science Foundation of China (51673087).

Underneath the unique and beautiful structures of biominerals there is always the presence of organic molecules that tightly interact with the developing inorganic nuclei/crystal directing its growth and assembly towards the final structure. This close interdigitation between organic and inorganic matter renders biominerals not only unique in their appearance but also with exceptional properties. A notable case of such combination is observed when combining double hydrophilic block copolymers (DHBCs) with different ions. In the particular case of calcium phosphate systems, the incorporation of DHBCs was found to induce the formation of unique and delicate neuron-like structures. The present article highlights that such structures are more common than probably expected and they can be created using much simpler organic molecules of a wider nature such as non-ionic surfactants (Tween 80 or Span 20), anionic polymers (sodium polyacrylate) and cationic polymers (polydiallyldimethylammonium chloride). The reaction conditions are however crucial in the stabilization of the structures.

Hydrogel coating has been attractive to improve titanium implants’ compatibility with biological surroundings and their performance in clinic. Herein, a CaCO3 layer is fabricated at the interface of hydrogel–titanium to achieve strong interfacial bonding. This strategy does not require complicated surface modifications and has good prospects in the field of biomedical applications.

The increasing emissions of carbon dioxide (CO2) are primarily driven by the rapid expansion of energy-intensive sectors such as the chemical industry. This work selects ethylene, one of the most important chemicals, as a model study to represent the low-carbon roadmap of chemical production. Four strategies improving the efficiency of fossil resource usage, developing the technology for carbon capture and storage (CCS), CO2 chemical conversion, and converting biomass resources into chemicals, are used to reduce CO2 emissions. A comprehensive analysis of the life cycle CO2 emissions of different ethylene production routes has been performed to compare their emission reduction potential. The results indicate that the BMTO (biomass to olefins via methanol-to-olefins) pathway releases the least CO2 (− 1.3 t CO2/t ethylene), while the CFTO (coal to olefins via Fischer-Tropsch synthesis) possesses the highest CO2 emissions. Combining CCS with BMTO results in CO2 emissions of – 8.2 t per t ethylene. Furthermore, we analysed the annual production and CO2 emissions of ethylene in the last 17 years and integrated this real-time change with different pathways. The CO2 emissions have decreased by 29.4% per t ethylene from 2000 to 2016 in China. However, the total amount of CO2 emissions continuously increases in ethylene production industry. Given that China has promised to hit peak CO2 emissions by 2030, a scenario analysis was performed. To achieve this goal, the ratios of BMTO, CO2MTO (CO2 to olefins via methanol-to-olefins) or BETE (ethanol to ethylene pathway originating from biomass) pathways should increase by 1.0%, 1.2% and 1.1% annually from 2020, respectively. Then more than 500 million metric tons of CO2 will be eliminated from 2020 to 2040. The results highlight the pivotal role that regulation and policy administration can play in controlling CO2 emissions by increasing average technological level and turning to low-carbon routes in the chemical industry in China.

Lignin is a renewable and abundant aromatic polymer found in plants. We herein propose a “cutting tail” methodology to produce phenol from lignin, which is achieved by combining Ru/CeO2 catalyst and CuCl2 oxidant via an oxidation–hydrogenation route. Phenol was obtained from separated poplar lignin with 13 wt % yield. Even raw biomass, such as poplar, birch, pine, peanut, bamboo willow, and straw, could be converted into phenol in 1–33 mg per gram of biomass.

Valuable polyester monomers and plasticizers-1,4-cyclohexanedimethanol (CHDM), 1,4-cyclohexanedicarboxylic acid (CHDA), and 1,2-cyclohexanedicarboxylates-have been prepared by a new strategy. The synthetic processes involve a proline-catalyzed formal [3+1+2] cycloaddition of formaldehyde, crotonaldehyde, and acrylate (or fumarate). CHDM is produced after a subsequent hydrogenation step over a commercially available Cu/Zn/Al catalyst and a one-pot hydrogenation/oxidation/hydrolysis process yields CHDA, whereas 1,2-cyclohexanedicarboxylate is obtained by a Pd/C-catalyzed tandem decarbonylation/hydrogenation step.

Biomass is renewable and the most abundant carbon resource, and it shows great potential for sustainable production of chemicals in the future. With respect to limited fossil reserves, biomass conv...

Life cycle primary energy demand (PED) and greenhouse gas (GHG) emissions for the production of propylene in China (year 2013) have been carried out by considering several propylene production routes into account, such as catalytic cracking (CC), stream cracking (SC), coal-to-olefins (CFO) and coal-to propylene (CTP), which cover the entire life cycle including: extraction and transportation of raw resources, preparation of feedstock, and production parts of propylene. The results show that the coal-based propylene pathway represents more PED and GHG emissions than the petroleum-based propylene pathway. The propylene production via CC route has the minimal PED, whereas CTO and CTP routes consume about 2.60 and 2.04 times energy of CC. Life cycle GHG emissions via four pathways are 1.60, 2.06, 12.16, 9.23 tCO(2) eq/t propylene, respectively. The coal gasification process plays a dominant contribution to GHG emissions via the coal-based propylene pathway and extraction process contributed the most via petroleum-based propylene pathway, which are the key factors for reducing the GHG emissions of life cycle of propylene. Adopting rectisol process of coal gasification prove effective, which can reduce 3239% and 26.14% life cycle GHG emissions despite increase about 3% energy. Meanwhile, it is also effective to reduce GHG emissions by enlarging scale of steam crackers. (C) 2016 Elsevier Ltd. All rights reserved.

A plethora of multi-view subspace clustering (MVSC) methods have been proposed over the past few years. Researchers manage to boost clustering accuracy from different points of view. However, many state-of-the-art MVSC algorithms, typically have a quadratic or even cubic complexity, are inefficient and inherently difficult to apply at large scales. In the era of big data, the computational issue becomes critical. To fill this gap, we propose a large-scale MVSC (LMVSC) algorithm with linear order complexity. Inspired by the idea of anchor graph, we first learn a smaller graph for each view. Then, a novel approach is designed to integrate those graphs so that we can implement spectral clustering on a smaller graph. Interestingly, it turns out that our model also applies to single-view scenario. Extensive experiments on various large-scale benchmark data sets validate the effectiveness and efficiency of our approach with respect to state-of-the-art clustering methods., Accepted by AAAI 2020

In the analysis and processing of image recognition, extracting useful and valuable data from the original dataset has become a problem. Since the data to be processed often presents high dimensional and nonlinear feature, reasonable dimensionality reduction is an necessary method for improving the accuracy of data analysis. One of the dimensionality reduction methods Kernel Principal Component Analysis (KPCA) has certain advantages in dealing with nonlinear data, but it also has defects when facing the dataset in which data owe highly complex relationship. The other linear dimensional reduction method Linear Discriminant Analysis (LDA) has supervisory characteristics, which can reduce the dimensionality of dataset in which data owe highly complex relationship. However it can only handle linear data. So we propose a hybrid method which is the combination of the above two methods called KPCA-LDA. By it the new dataset obtained by the step of dimensionality reduction is beneficial to be processed in next step for classification. We combine KPCA-LDA with the Back Propagation Neural Network (BPNN) method to achieve the classification of handwritten numbers. The experimental results show that the classification accuracy of the proposed KPCA-LDA-BPNN model can reach 98.67%, which is about 3%-5% higher than the original method using K Nearest Neighbor (KNN) and Support Vector Machine (SVM).

Biomass chemical industry potentially reduces fossil energy dependence and addresses climate change, however, reaching technical feasibility and economic competitiveness are still crucial challenges, especially in the conversion of lignocellulosic biomass. Herein, an early-stage analysis is conducted to evaluate technical, economic, and environmental benefits of ethylene glycol (EG) production from lignocellulose, which, for one representative demonstration, provides an insight into opportunities and constraints associating with the transition from lab testing to practical industrialization of biochemicals. With process design and modeling, techno-economic analysis, and life cycle assessment, the results reveal that lignocellulosic biomass-derived EG (bio-EG) is at present attractive in aspects of life cycle primary fossil energy depletion and greenhouse gas emissions, but the total production cost of bio-EG is 43% and 20% higher than that of coal-EG and petro-EG. To achieve the economic benefits of bio-EG, research strategies, such as raising the product yield, changing hydrogen sources, increasing feedstock collection efficiency, and lowing water consumption were explored and proved to be effective measures. In addition, a carbon tax of 184 and 598 CNY·t−1 CO2eq are the breakeven points to reach economic benefits of bio-EG compared to petro-EG and coal-EG, respectively. This work aims at conducting a comprehensive evaluation of bio-EG to promote its practical application, and also shedding light on bright prospects and general approaches to develop lignocellulosic biochemicals.

Human hair keratin (HHK) is successfully exploited as raw materials for 3D scaffolds for soft tissue regeneration owing to its excellent biocompatibility and bioactivity. However, most HHK scaffolds are not able to achieve the anisotropic mechanical properties of soft tissues such as tendons and ligaments due to lack of tunable, well-defined microstructures. In this study, directed ice templating method is used to fabricate anisotropic HHK scaffolds that are characterized by aligned pores (channels) in between keratin layers in the longitudinal plane. In contrast, pores in the transverse plane maintain a homogenous rounded morphology. Channel widths throughout the scaffolds range from ≈5 to ≈15 µm and are tunable by varying the freezing temperature. In comparison with HHK scaffolds with random, isotropic pore structures, the tensile strength of anisotropic HHK scaffolds is enhanced significantly by up to fourfolds (≈200 to ≈800 kPa) when the tensile load is applied in the direction parallel to the aligned pores. In vitro results demonstrate that the anisotropic HHK scaffolds are able to support human dermal fibroblast adhesion, spreading, and proliferation. The findings suggest that HHK scaffolds with well-defined, aligned microstructure hold promise as templates for soft tissues regeneration by mimicking their anisotropic properties. Agency for Science, Technology and Research (A*STAR) Accepted version This research is supported by the Agency for Science, Technology and Research (A*STAR) under its Acne and Sebaceous Gland Program & Wound Care Innovation for the Tropics IAF-PP (H17/01/a0/008 & H17/01/a0/0L9).

Human hair keratins (HHK) are known for their biocompatibility and potential to regulate cell response, possibly due to the presence of the leucine-aspartic-valine cell adhesion and signaling motifs. Together with the abundance of cysteine residues in HHK, 3D HHK scaffolds are fabricated through cryogelation based on spontaneous disulfide crosslinks and noncovalent interactions. Herein, the molecular mechanism of HHK self-assembly during cryogelation is interrogated and the influence of cryogelation parameters on the properties of the resultant scaffolds is studied. With successive freeze-thaw cycles, the storage modulus (G') of HHK cryogels substantially improves from 116.4 Pa at freeze-thaw cycle 3 (FT3) to 1908.7 Pa at freeze-thaw cycle 10 (FT10). Meanwhile, it is found that complete thiol-capping of HHK samples significantly inhibits cryogel formation as compared to partially or uncapped HHK samples, suggesting the dominant role of disulfide stabilization in cryogelation. Finally, uniaxial compression tests on HHK sponges demonstrate that FT cycling, from 0 to 10, is able to improve the compression modulus of sponges by ≈12-folds. These findings show that macroscale properties of HHK cryogels can be conveniently modulated by physical parameters of cryogelation and that disulfide bonding is the main stabilizing force in HHK cryogels. Agency for Science, Technology and Research (A*STAR) Accepted version This research is supported by the Agency for Science, Technology and Research (A*STAR) under its Wound Care Innovation for the Tropics IAF-PP (H17/01/a0/0L9). The authors would like to acknowledge the Facility for Analysis, Characterization, Testing and Simulation, Nanyang Technological University, Singapore, for their technical support in scanning electron microscopy analysis.

Ingestion of engineered nanomaterials (ENMs) is inevitable due to their widespread utilization in the agrifood industry. Safety evaluation has become pivotal to identify the consequences on human health of exposure to these ingested ENMs. Much of the current understanding of nanotoxicology in the gastrointestinal tract (GIT) is derived from studies utilizing pristine ENMs. In reality, agrifood ENMs interact with their microenvironment, and undergo multiple physicochemical transformations, such as aggregation/agglomeration, dissolution, speciation change, and surface characteristics alteration, across their life cycle from synthesis to consumption. This work sieves out the implications of ENM transformations on their behavior, stability, and reactivity in food and product matrices and through the GIT, in relation to measured toxicological profiles. In particular, a strong emphasis is given to understand the mechanisms through which these transformations can affect ENM induced gut nanotoxicity. Nanyang Technological University Accepted version Nanyang Technological University—Harvard School of Public Health Initiative for Sustainable Nanotechnology (NTU‐Harvard SusNano).

Quinazolinones, an important class of heterocyclic compounds, have been widely used in pharmaceuticals because of their biological activity. However, the efficient and economical synthesis of quinazolinones has remained a challenge. A novel synthetic approach has now been developed to produce quinazolinones from olefins, CO, and amines over heterogeneous Ru-clusters/ceria catalyst in the absence of acids, bases, and oxidants. Furthermore, H2 O is generated as the only by-product. A series of quinazolinones with aromatic or non-aromatic substituents can be obtained in yields of up to 99 %. The Ru-clusters/ceria can be reused at least four times. The analysis of the E-factor (environmental impact factor) for the synthesis of 2-ethyl quinazolinone suggests that this system is more environmentally friendly than other processes reported previously.

Over exposure of UV light could cause serious damages to human being, such as DNA damage, skin aging and cancer, cataract and so on. Hence, there is an urgent need to develop optically transparent materials as windows, glasses and protection film etc. to filter UV light. In the present study, a homogeneous polyvinyl alcohol (PVA)/zinc oxide (ZnO) film was fabricated via a facile in situ method by controlling the reaction of Zn2+ with OH- ions and the dehydration process of Zn(OH)42- throughout PVA hydrogel matrix. The obtained PVA/ZnO film can absorb over 99% of UV light at wavelength region between 200 and 350 nm, and its optical transparency in the visible region was similar to that of neat PVA film (87–90%). In addition, this hybrid film was flexible (~5% strain at fracture) with excellent tensile strength (130–140 MPa), and able to be easily modulated onto various substrates as UV-protection film. Overall, this facile, low cost in situ fabrication method with environment-friendly nature could be applicable to various hydrogel systems for developing novel transparent UV-shielding nanocomposites with desired properties.